It is well known to hot press cellulose sheets (papers) impregnated in phenol or melamine (or similar-resins) with wooden boards or panels (plus other components specified by the manufacturer) to produce products such as boards, laminated boards, panels, and direct laminated floors that imitate wood, ceramic, and natural stone. Such imitation materials are mainly used for floors.
If melamine is used, and if the product is to have a single work surface (for example a floor), the melaminized board that comes from the press typically has a surface area between 3 and 8 square meters. Such boards are then cut into units (strips) approximately 1,200xc3x97200 mm. Each unit is beneficially tongued and grooved for ready installation. The result is a decorative and resistant paving that imitates wood, ceramic or natural stone.
Such known products have two significant defects:
1. They are not very wear resistant.
2. They do not closely imitate natural products (such as ceramic and wood).
The applicant has investigated reason why such products are not very wear resistant. It has been observed that premature aging (wear) begins at or near the perimeter edges and/or along tongue and groove lines.
The known products have an even (level) surface texture such that the user, such as a pedestrian, treads (the soles of his shoes make contact) equally on the center of a tile on its perimeter edge. But, since the perimeter edge is the weakest area it deteriorates first.
The applicant has also investigated the reason for the second defect. He has reached the conclusion that if an imitation product is not a suitable imitation of a natural product, it is at least partially because the imitation""s surface texture, both optical and tactile, have design errors.
In current products, a decorative surface effect is achieved by a design that is printed on an impregnated (by resin) paper. However, the surface texture of products with such printed designs is typically monotonous (flat) over the whole surface. This is because the press mold produces a flat surface.
Thus, while a surface design represents the different characteristics (line, color) of a natural product, the texture (relief) provided by the press mold does not match a natural product""s surface level variations, both with regard to sight and to touch .
One object of the invention is to overcome the wear problem of products (tile, strip, board, etc.), which typically have a polygonal shape such as a rectangle or square. The object is achieved by providing a relieved perimeter. That is, a product""s perimeter edge is contoured to be a few tenths of a millimeter below the rest of the product""s surface. Thus, when a user treads on the product the user""s soles do not rest on the perimeter edges. Likewise friction or wear caused by other agents coming into contact with the product is avoided.
Another object of this invention is to overcome the problem wherein a product""s surface (such as that of a tile, a strip, or a board) is totally even or monotonous. This object is achieved by producing a product having a surface texture that corresponds and adapts to a printed design. The result is close optical and textural identifications with a natural product.
That is if, for example, a wood knot appears in a design the final product is adapted to that design by providing an area having a volumetric, conceptual, and physical correspondence, both visual and textual, with a wood knot. A similar thing happens if there is a wood pore, a stone roughness, or bubbles on a ceramic.
The foregoing is achieved using an exact correspondence-concordance between the image on the impregnated papers and the relief texture of a press mold.
Example,
a). Ceramic tiles in which the unions (joints) between tiles are relieved to produce a paving of earthenware ceramics;
b). Wood designs where the streaks, pores, and knots of a paper design coincide with the surface texture.
In short, products with a very marked surface texture that adapts and corresponds to the design on a resin impregnated paper. What is achieved is a more realistic affect than when the surface texture does not adapt and correspond to the design on a resin impregnated paper. Not only is an optical effect created, but also the different reliefs, which appear in the correct areas, can be touched.
Also, the product""s life increases as relieved joints do not undergo wear. This is because the relieved joints are not contacted when being trod upon.
This invention advocates new direct laminated flooring of cellulose sheets impregnated with polymerizable resins and having design characteristics, and that, once pressed, have offset/sunk areas in peripheral edges.
This invention is also characterized because the optical/tactile texture of the surface of the floor, once pressed, corresponds and adapts to the characteristics designed on cellulose sheets.